Pottery fabricating machine



June 10, 1952 J. A. BowER POTTERY FABRICATING MACHINE original Filed March 1, 1945 9 Sheets-Shea?l l "nf/w- INVENToR.

ATTORN EY. 4.

June 10, 1952 A. BowER 2,599,605

POTTERYA FABRICATING MACHINE original Filed Marchv 1, 1945 9 sheets-sheet 2 INVENTOR.

Jamas A. ,Bowelo ATTORNEY June 10, 1952 J. A. BowER POTTERY FABRICATING MACHINE original Filed Mar-ch 1. 1945 INVETOR, cfameA. ,Bower ATTORN EY.

June l0, 1952 J. A. BowER 2,599,605

POTTERY FABRICATING MACHINE Original Filed March l, 1945 9 Sheets-Sheet 4 INVENTOR. c/wzes A. ,Bower ATTORN EY June 10, 1952 JQ A. BCM/ER 2,599,605

` POTTERY FABRICATING MACHINE 9 sheets-sheet 5 original Fileduarch 1, 1945 N Jmeo A. ower "n Q D N BY wz ATTORNEY June 10, 1952 J. A. Bowl-:R 2,599,605

POTTERY FABRICATING MACHINE Original Fil-ed March l, 1945 9 Sheets-Sheet 6 INVENTOR.

C/m ed' A ower 25u/6fm ATTORNEY J. A. BOWER POTTERY FABRICATING Junelo, 1952 MACHINE 9 Shees-Sheet 7 original Filed March 1, 1945 INVENTOR ATToRNEY J. A. BowER POTTERY FABRICATING MACHINE June 10, 1952 9 Sheets-Sheet 8 Original Filed March 1, 1945 June 10, 1952 J. A. BQWER 2,599,505

POTTERY FABRICATING MACHINE Original Filed March l, 1945 9 Sheets-Sheet 9 Patented June 10, 1952 2,599,605 POTTERY FABRICATING MACHINE James A. Bower, Chester, W. Va., assignor to The Taylor, Smith & Taylor Company, East Liverpool, Ohio, a corporation of West Virginia Original application March 1, 1945, Serial No. 580,401. Divided and this application April 9, 1947, Serial No. 740,360

8 Claims.

1 The invention relates to a pottery fabricating machine, and this application is a division of my application Serial N o. 580,401, led March l, 1945, and now abandoned.

My application Serial No. 580,401 discloses a completely automatic and integrated machine for fabricating pottery of either the vitreous or semivitreous type, and which is particularly Well adapted to carry out the invention described and claimed in my Patents Nos. 2,273,015 and 2,273,016, granted February 17, 1942.

In the machine disclosed in my application Serial No. 580,401, the `molds are placed in trays and the trays are caused to travel step-by-step through the machine, and al1 operations necessary for complete fabrication of the ware, such as cleaning the molds, pouring the slip, opening and closing the molds, drying the ware, removing, fettling, inverting and stacking the ware, etc., are performed automatically.

The present application does not relate to the operations of cleaning the molds, pouring the slip, opening'and closing the molds, drying the ware, removing, fettling, inverting and stacking the ware, but rather it relates to the construction of the machine itself, the mechanism for operating the machine, the means by which the trays are carried through the entire machine comprising a number of vertically spaced tracks, etc.; the construction and arrangement being such that all operations necessary to the complete fabrication of the ware may be performed during the passage of the molds through the machine.

Various objects and advantages of the invention will be apparent to those skilled in the art from the following description when taken in connection with the accompanying drawings, in which:

Figure 1 is a perspective view of the pottery machine with an intermediate part broken away;

Figure 2 is a side elevational view of the power end of the apparatus;

Figure 3 is a perspective view of the power end of the apparatus with the upper portions thereof broken away;

Figure 4 is a fragmentary perspective view, on an enlarged scale, of the power end of the apparatus;

Figure 5 is a perspective View of a portion of the opposite end of the apparatus with parts removed, for the sake of clearness, and showing on an enlarged scale the means for engaging and restraining the end trays of a series of mold trays;

Figures 6, 7, 8 and 9 are detail views of the means for temporarily engaging and restricting the trays at the ends of each series of trays;

Figure l0 is a fragmentary perspective View of the mechanism for operating the vertical conveyer at the rear or power end of the apparatus;

Figure 11 is a fragmentary' plan View of the gearing shown in Figure 10;

Figure 12 is a perspective View of a pair of hooks forming latching meansI for interlocking a tray on one of the vertical conveyers;

Figure 13 is a detail elevational view of the tray latch and associated mechanism for automatically releasing the same at the proper time; and

Figure 14 is a diagrammatic view of the hydraulic system for operating the weight and associated parts for causing the mold trays to travel through the apparatus in a substantial harmonic motion, step-by-step.

Before proceeding with a description of the details of construction and operation of the apparatus it is deemed desirable to describe in a general way both the structure and the main operational features of the machine as a whole.

As previously stated, the machine is designed for casting pottery and is entirely automatic including the initial step of lling the molds with slip and the final step of fettling the ware and placing it on a conveyer in stacks of proper height, ready for firing in the kiln.

The main frame of the apparatus as shown in Figure 1 comprises a track composed of ten vertically spaced track sections or guideways, hereinafter referred to as tracks, upon which mold-carrying trays, such as shown at the left of Figure 4, are pushed along in a step-by-step movement, so as to provide dwell points or stations, throughout the continued operation of the apparatus. As each tray reaches the end of a particular track, except the top one, it is moved upwardly to the next track, by vertically disposed conveyers at opposite ends of the machine. The entire period of movement and rest comprises less than ten seconds.

While there are ten vertically spaced tracks in the embodiment illustrated, it will be understood that the number of tracks depends on the space available. Thus the machine may be lengthened to reduce the number of tracks as desired, if sufficient space is available, and thereby reduce the number of times the trays must be transferred.

In the specific embodiment of the invention illustrated, a substantial simple harmonic stepby-step movement is imparted to the trays by means of a heavily weighted pendulum operated by an hydraulic system, shown in Figure 14, which also operates the elevators at the opposite ends of the apparatus. The operation of Y of Figure 4, mounted on each tray and each mold comprises upper and lower sections. At a certain stage of the process the` upper mold sections are unlatched and removed from the lower mold sections and placed beside them on the tray.

The mold sections are assembled and latched together at the right of the lower or No. 1 track in Figure 1. The trays with the closed molds are then moved successively to the second o r No, 2- track by a vertical conveyer at the right of Figure 1, wherethey are filled with measured quantities of slip. Thereafter the charged molds travel along tracks Nos. 2, 3, 4, 5, 6, during which time substantial quantities of moisture in the slip is being absorbed by the walls of plaster-of-Paris molds or other porous molds. On the sixth track automatically operated mechanisms are provided for removing eX- cess slipA from the funnels of the molds and for unlatching and removing the upper mold sections. The fully formed and exposed ware is then automatically stampedwith a trade-mark or the like and travels through an enclosed zone ooricfieio 7j, d., il, and. 1,0, where heated air is directed on theware, to dissipate residual moisture therefrom. 'After leaving the drying Zone the. trays. descend on the endless vertical conveyer at the leftoffrfEigurle l, where takeeout mechanisms are provided for. removing theware from the molds, ettlingfth'e" ware, inverting. it and stacking it on a cohyeyer in the proper height stacks, ready for firing irl the kiln. The trays of empty molds a til-.eli Placed on the lowermost track and gradually movedin Step-.ty-Steprasruon through a.Vv heating Zone and to the mold assembling apparatus mentioned hereinbefore, at which pointr process is initiated. The

a repetition of the various operations on the molds, such as filling, disassembling, drying, etc., are of course performed during the dwell periods. of the` molds in. their travel through the machine. All the 1nechanism for performing. all of the operations.

l ,Y tionedY above is shown. in my parent applicaftmn,V Serial No. 580,401. The presentl divisional application relates mainly to the machine itself,v the' mechanism for driving the machine, carrying the trays loadedV withv molds along the ii yricjustracks where the numerous operations areVv performed, the transfer of the trays from one' track to. another, etc., and hence only thcse parts which are pertinentto the subjectfrnatter hereof, are describedl herein. And while these are described in considerable detail such detailed disclosure isintended as illustrative only andA not in. any limiting sense.

The trays are indicated by numeral l, and as sho vn af the left of: Figure 4 they are relativelyflong and narrow and are composed of longitudinal side bars 2 or angle formation which are united at their respective ends by the end 3f The bars, 3` are slightly longer than the g a portion oftrack 6 and tracks Nos.V

width of the trays so as to provide end portions which contact similar portions of adjacent trays when passing along the tracks of the apparatus and which also provide a slight space between the side bars of adjacent trays.

Each tray is designed to carry six molds through the apparatus, although itV will be understood that this number may be increased or decreased as desired. The molds are composed of upper and lower sections 5 and 6 respectively, as shown at the left of Figure 4, where an upper mold section has been removed from a lower moldv section and positioned beside it on the tray. The mold sections are in the form of metal rings of angular cross-section to which are molded sections 'l and S made of P1dSterofParis or other porous material which form the mold cavity. Each of the upper mold sections is provided with a charging or filling funnel 20 which is permanently imbedded in the plaster-of-Paris and which opens into the interior of the mold. No further description of the molds is necessary herein, as the molds are the subject-matter of another divisional application Serial No. 749,105, filed April 8, 1947, and now Patent No. 2,526,993, granted October 24, 19.50.

A description of the general framework of the apparatus, as disclosed mainly in Figures 1, 2 and 3, will now be given.

The foundation of the apparatus is preferably composed of a suitably prepared flooring 25. (Figure 2) on which certain of the vertical standards are supported. Concrete blocks or base members 2,5are preferably provided at the power end of the apparatus for supporting the heavier parts of the mechanism.

Shallow.. wells 21. may loe Provided. in. the floor at opposite ends. of the apparatus to permit the installation of the lower endsof they vertical cone veyers or elevators, as will later appear.

Mounted on the blocks 26 die horizontal beams 28 from which are supported the osollatablrmounted weight and related` parts` which function to impart the step-by-stepmovement to the trays andthe molds carried thereby. Extending vertically from the blocks 2,6 are a plurality of standards 2,9, and together with similar Stande ardsll. (Figure l) based on the floor 2.5, provide Supports, fory the horizontal beams. 3l.

There are. twenty of the beams 3l, ten on each side of the framework and they arefarranged in` horizontal pairs,r spaoed vertically, to provide ten trackwaysfor themold` trays. Each' beam hasV mounted thereon a series. of` rollersV 32. on which the trays are causedto ride in their travel through thev apparatus.- As previously. mentioned, the trays` onfeach'track arein contact with each other and the entire series, on each tracky is caused to move forward one VStep ata time. by a pusher -bar provided for. each` track. Therefore, in order to prevent: buckling of a series of trays as it is pushed along.. its.

track` aplate 33 (Figure 5).v is4 mounted on each beam and, extends lengthwise thereof inoverhanging relation to the rollers 32.; the space1 Nos. 1, 3, 5 '7 and 9 to the. right (Figures 1. andv 2), and five for moving the trays on tracks Nose f 2, 4, 6.3. and 10 to` theleft, These` pusher bars are rather massive affairs and are substantially rectangular in form, comprising side bars 34 and cross bars 35. The side bars 34 are mounted to slide on krollers 35 supportedon the standards 29 and 30 of the main frame, and rollers 31 (Figures 5) are also mounted on the standards to engagethe outer sides of the bars and thus guide these members. The pusher bars of each series may be rigidly connected by vertical braces, if desired.

Each cross bar 35 of a pusher bar is provided with a pair of rigid lugs or ngers 38 adapted to engage the adjacent side of the end tray `of the particular series and move the entire series through the distance of movement of the pusher bar. The pusher bars of tracks Nos. 1 and 2 are provided with extensions 35 and 40 on which are formed racks 4|.and 42 which cooperate with pinions 43 mounted on a shaft 44. Rollers 45 and 46 may be mounted on the main frame to engage opposite sides of the racks to maintain them in proper relation to the pinions. Also fixed to the shaft 44 are pinions 41 cooperating with racks 48 carried by the piston rods 49 of hydraulic cylinders 50 and 50a. These piston rods are formed with a reduced portion or extension 49 providing a shoulder whereby certain switches, which form no part of the present invention, may be operated. The main operative force applied to the shaft 44 is a weight or pendulum bob 5| rigidly suspended from the shaft by arms 52. This weight may be formed of metal, concrete or the like and weighs several tons, although the exact weight will of course depend upon the number of trays, molds, etc., employed in the particular installation. Obviously, power in addition to the pendulum must be employed to maintain the apparatus in operation and this additional power may be in the form of a hydraulic system of which the cylindres 50 and 5l]at form a part. It should be noted however that by use of the pendulum the power required for acceleration and deceleration of the mold trays neutralize each other, thus requiring the use of only sufli'cient power to move the load at a uniform continuous speed. The hydraulic system will be described hereinafter.

The series of trays on tracks Nos. 3 to 1'0 inclusive are operated simultaneously with the trays on Atracks Nos. 1 and 2, and to this end the shaft 44 is provided with bell-crank levers 53 xed to its opposite ends. One end of each of these levers is connected to vertically extending rods 54 on opposite sides of the machine. The pusher bars for tracks Nos. 3 to 10 are provided with racks 55 similar to those employed with the pusher bars for tracks Nos. 1 and 2,and pinions 51 are employed for causing adjacent pusher bars to operate in opposite directions. In order to operate the pinions 51, alternately plain and bell-crank levers 58 and 59 respectively may be connected with the pinions and with the operating bar 54, the opposite ends of the bell-crank levers being connected to the rod 55. The sole purpose of the rod 55 is to maintain the operating rod 54 in vertical position, and this is accomplished by the use of the bell-crank levers for connecting the rods at spaced points.

The movement of the molds through the apparatus is an intermittent one, there being a substantial simple harmonic movement of all of the molds simultaneously along the tracks, then a period of dwell, and then a repetition of the movement. A complete cycle of operations, that is, the period of movement and dwell, ordinarily requires about ten seconds, but the timing of course may be varied as desired. The substantial harmonic movement is provided by the action of the pendulum 5|52 (Figures 3 and 14). and the pendulum is temporarily maintained at the limits of its swing, particularly the rear swing, by the cylinders 50-50t Also, in order to avoid accidents, and to sustain the pendulum when the machine shuts down, weight locks 60 are provided. There are two of these locks or supports for cooperation with the weight at the end of its rear stroke, and they are located adjacent the ends of the weight on opposite sides of the apparatus. The locks 60 are slidably mounted on the main frame of the machine and are operated by hydraulic cylinders 6I (Figure 3), in timed relation with other parts of the apparatus, preferably by anelectric circuit which'forms no part of the present invention.

As the mold trays I reach the end of each of tracks Nos. "l to 9 they are raised to the next track above, and from track No. 10 they are moved to a ware removal and finishing station and then to a firing kiln. To accomplish this step-by-step movement of the mold trays` a vertical conveyer or elevator is provided at each end of the apparatus and each is operated in timed relation with the pusher bars, etc., by the hydraulic system heretofore referred to.

The structural details of the elevators and their related parts will now be described, but inasmuch as they are substantial duplicates a description of one of them will sullice, except as to certain variations in structure or operation.

Each elevator comprises a pair of endless sprocket chains 55 cooperating with upper and lower pairs lof sprocket wheels 56 and 61 respectively (Figures 1 and 2), the latter being posi--V tioned in the wells the machine and the former being mounted on the main frame of the machine at points slightly higher than the uppermost track No. l0. A lower shaft of each elevator is also provided with a cam wheel 61a (Figure l) having four circumferentially spaced lobes for operating switches in an electric control system Vertical guideways 68 are provided to prevent lateral movement of the chains 65.

Pivotally attached to each pair of sprocket chains is a uniformly spaced series of shelves for supporting the trays I. These shelves, shown on an enlarged scale in Figure 12, are spaced along the chains at a distance corresponding with the spacing of tracks Nos. 1 and 2, or 3 and 4, etc., and the chains of course are spaced apart a distance corresponding substantially to the length of the mold trays. Each shelf comprises a pair of links or hangers 69, one pivoted to each chain, and rigidly connected to each other by a cross bar 10. Rigidly connected to each hanger is a shelf section 1I. Each pair of chains of an elevator is operated in a direction which willcause the flight nearest the tracks to move upwardly and the remote flight to move downwardly.

The mechanism for operating the eleva-tor at the right hand end of Figure 1 is shownin detail in Figures 10 and 11, and -is identical-with the mechanism for operating the elevator at the power end of the apparatus, except that the latter has no brake release, as will later appear. This driving mechanism will now be described.

Suitably supported on the main frame of the apparatus adjacent the top of the elevator is a base plate 15 (Figure l0) on which is rotatably mounted a pinion 1li.` The shaft of pinion 16 21 at the front and rear of is provided. with a crank-arm. 11, the free end 'i'.'l-lereof being pivotally connected to an arm 18.

Fixed to the shaft of the 'adjacent sprocket wheel 66' :is a gear wheel19 to one face of which are attached. four uniformly spaced pins or lugs 8i) adapted to cooperate with the arm 18. For this purpose the arm is formed. with a reduced portion at its end to provide a pin engaging' shoulder 8l, Movement of the arm 1.8 to the right (Figiure: 110) will impart a rotary movementl to the sprocket 16 and thus cause the elevator to operate. Movement of arm 18` to. the. left will have no effect on the sprocket wheel, but it will be noted that the arm is of such length that it will remain: supported by one of the pins Von its 'retroa grade movement. Oscillation of the pinion 16 and crankear-m 11i is obtained b'y means ofY a hydraulic cylinder 82 and a rack 83 connected to the piston rod of the cylinder.

The length of stroke of vcylinder 82 is such as will:y impart to the elevator a movement corresponding to the distance between: tracks Nos. l and. 2, etc. Necessary adjustments mayy of course. be made inthe stroke of the cylinder or in the connectionv between arm 18;, so as to provide the desired flexibility of action required to. bring the mold trays and shelves into alignment with the various tracks.

For the purpose of maintaining the elevator stationary after each operation a bra-ke has been provided. In' the` present construction the brake is intheform of a brake drumV 8d xed to a shaft -85 whichalso carries a spur gear 86 meshing with gears-wheel 19 secured to the sprocket shaft. Cooperatingv withbrake drum 8f#k is a brake shoe B1 fired to; the underside ofV a pivotedy arm 88. A weight 89 is secured.v to the free end.v of arm 83 and: provides thek necessary' frictional contact between the braking elements 84 and 81. Release of the brake mechanism is obtained by meansofv a hydraulic cylinder' S0, and it willbe understood that thiscylinder as well as cylinder 82, mentioned above, are operated in timed relation: with other partsfotk the mechanism. o

Mounted enthe. exterior' face of the v.sprocket wheel 85- on the opposite end of the shaft carrying the gear wheel 19Vare four pins 9| spaced in the `same manner as the pins l8!) mentioned above. Thepins 9i function to close a switch in anelec tric'` circuit to indicatethe proper position with theytrays: level vwith the tracks. A pawlor latch '92, with al rounded nose 93; isy provided to engage with rounded notches between thefteeth ofy one of the sprocket wheels; a weight 94-maintaining -the nose in en- The purpose gagement. with the procket wheel. o

of the elevator.

Oflatch 9% is to prevent movement ifthe brake. should f ail.

Thefdrivingmechanism iorthe elevator at the power end of theapparatus is substantially identical with..that just. described, exceptthat no means is provided forv releasing the brake.V This isdue tofthefact thatthe elevator at the power end of the apparatus. isV` rnoienearly in equilibrium by reason of-the presence of trays on .both its. upwardly moving: and downwardly. moving flights, whereas, the other elevator supports trays on kits upwardly moving. flight only, .as willappear hereinafter. v u

The details ofv the driving mechanismfor the elevatorsv hasv been describedA at. considerable length, but it is.. intended. that. me disclosure be considered. asillustrati-ve rather than inV alimitingsense. u Asuneicatecbn the drawings, the suaves 1| the crank-arm 11 and f that. the elevators are in 8 are provided with no anges to prevent Alateral movement of the trays I' ldue to vibrations or jarring `of the machine, etc. Moreover, such cnnv` iin'ement of the trays would be impossible due to the fact that they must be pushed on aridon the elevators, by the pusher bars 35, when being transferred from one track to another. Accordingly, automatically releasable interlocking means has' been providedv for preventing accidental movement or dislodgement of theA trays from the elevator shelves, Such' means is shown in detail in Figures 12 and 13; and comprises a shaft `95 rotatably mounted in bearings S16 on the shelf 1I.` A pair of outwardly directed fingers 91 are formed 'on the shaft 95 and are spaced longi-` tudinally of the shaft a distance corresponding` substantially to the width of the space between the side walls of a tray' I. A coil spring 98 serves. to bias the shaft in a direction to cause theV ngers 91 to interlock with the corners' of the tray. To releasev the tray, a cam 99' is nxed to an end of shaft S5 and is 'adapted' to engagea lock release bar IDB", thereby rotating the shaft 95 against the ten-sion of spring 98 and depressing the fingers 91 to a position below the tray l. It

will be understood of course that the lengtli and position of the release bar l is such that the fingers 91 are inoperative position when theele-4 vatorsJ are moving, and arel in inoperative position when they elevators are stationary, thereby perl mitting the loading or unloading of t-hetrays' onto and off of the elevators.

Itis alsol essential that the trays i be accurately positioned on the elevator shelves when-reaching each trans-fer position so' as to prevent accidental engagement with thev pusher bars 35 and other parts of the apparatus.; To thisend, vertically extending guide bars |01A (Figures 5 and 9).- are provided; These bars are inclined towards each other at their upper ends, as indicated'v by numeraL |82', and serve to insure'the eXact'pos-itioning of the trays as` they arrive at the various stations for removal onto the*I severaly tracks:

Upon the movement ofa meldt-ray from an elevator shelf onto a track` as byoperation. of apusher bar 35; it is desirabley that means be providedfor temporarily holding the tray in` its new position until such time as-it is moved- -forwardly by. the next tray being pushed-offthcjelevater onto thetrack atthe next operation ofthe apparatus; otherwise there isthe liability that the tray may be 4jar-redbackwardlyA on" the track orA at' least into the' line of movement/of the elevator, thereby` causing considerable damage and disruption` of operations. This'function-is providedby means cfa pair of pivotedlatchesjadjacentthel rear end-- o'f each track,L operated by the respective pusher bar; one latch being mountedat each side ofthe track. o w

A rlS-hese. latches are` shownY in detail in Figures 6to9inc l usive, and. consist` primarily of as'ha'ft irrotatablyv mounted in--a bearing. IG-on each side of .the lrnai'n frame of the machine, and pro-'- videdwithlo'cki'ng fingers lHST on-the'ir inner ends for engagingaY tray lj, andV anr operati-ng arm ill-8 on their outer ends for cooperation with suitable mechanism depending froml each side armr of the pusher bars. The operating meansA 4for the latchescomprises arigid arm or plate I'VI-eX'- tendingdiwnwardly fromeacl'ar'r'nl cfa pusher barV r35 andV provided with aspring-pressedplate l il acingtowardthe operativeend-of the ypusher bar. A-cammeznber II`2' in the form off arod provided. Vwithlan4 offset portion l-l 3', has one endsecured to thelpusher bar anditsopposite endto the lower end of the plate H0. The arm |08 of the latch is in the path of movement of plate and cam H3 as the pusher bar moves back and forth in its operations of moving trays from the elevator to the particular track in conjunction with which it operates. As Will be noted from an inspection of Figures 7, 8 and 9, the arm |08 of the latch rides up on the rod H2 shortly after the pusher bar initiates its transfer of a tray from the elevator to a track, thereby releasing the tray previously moved forward from the elevator, and maintaining the locking fingers depressed until such time as the pusher bar approaches the limit of its return movement. In this latter position the arm |08 rides down the cam H3 and is engaged by the spring plate H I which causes the nger |01 to engage the inner side of the wall of the tray just placed on the track, and maintains the tray against accidental displacement until the pusher bar is again operated. This operation of the fingers 01 also projects the tray against the previously loaded trays and tends to take up any slack in the series of trays, which may have been caused by jarring or the like created by action of the pusher bars. The dotted line positions shown in Figure 9 indicate the positions of the several parts at the time the fingers |01 first engage the tray.

In the course of pushing a mold tray from an elevator shelf onto a track it will be understood that the whole line of trays on the track is moved forwardly one step and that the foremost tray is pushed off the track onto the elevator at the far end of the track. Accordingly, it is necessary that means be provided to control the movement of the tray leaving the track so that it will be 4properly placed on the elevator shelf, and will not prematurely reach the line of elevator movement. Also it is desirable that the entire line of trays be compacted prior to the initiation of the forward stroke of the pusher bar. For this purpose each pusher bar is provided with a pair of hydraulically-operated levers or hooks at its remote end, one on each side of the pusher bar frame. These levers also serve in conjunction with the pendulum to apply the decelerating force of the pendulum to the tray lines.

The sequence of operations of the hooks is shown in Figures 7 and 8, and the construction thereof is shown in Figure 5. Each hook comprises a lever H5 pivoted on a plate carried by the pusher frame and provided with a roller H6 mounted on its free end. The opposite end of the lever is pivotally connected to the piston rod of a hydraulic cylinder which latter is mounted on a bracket fixed to the frame of the particular pusher bar. The valve controlling the admission of oil or the like to cylinder l is operated by the timing drum of the electric circuit.

In Figure 8, the pusher bar is shown in its retracted position on each of two tracks and each is ready to push a tray onto its track as soon as the tray is brought into horizontal alignment with the track by the elevator. Just prior to the forward movement of the pusher bar the cylinder H1 will operate to move the lever H5 about its pivot and bring the roller H6 into engagement with the inner wall of the 'end tray. The lever is operated with sufficient force to take up any slack in the line of trays, the tray at the opposite end of the series being held against movement by the fingers |01 heretofore described. It will thus be seen that the entire series of trays is. clamped between the pair of hooks at the rods to keep up with and `10 forward end of the series and the pair of fingers at the rear end of the series, and that buckling of the trays is prevented by the plates 31 which `are fixed to the main frame of the apparatus and overhang the ends of the trays. With the series of trays thus encompassed and clamped together the pusher bar 35 moves it forwardly as a unit, removing a tray from the adjacent elevator onto the track and removing the remote tray of the series from the track onto the remote elevator. This latter condition is shown in Figure 7, and the hooks H5 have been raised so as to permit the pusher bar to return to its initial position. When the pusher bar reaches its rearmost position the lever arm |08 will be engaged by the spring plate so as to raise the fingers |01 and lock the tray which has just been moved onto the track.

The mechanisms for moving the trays in their general course through the pottery machine have been described, and I shall now describe that part of the hydraulic system which relates directly to the propulsion of the trays through the apparatus, namely, that part of the system which operates the pusher bars and the elevators at the opposite ends of the apparatus.

As heretofore mentioned, the main source of power for operating the several `pusher bars is the weighed pendulum 5| 52 which functions to provide a slow start and stop to the lines of trays and a relatively rapid movement between the start and stop; the pendulum being momentarily halted at the end of its rear swing to prolong the interval of time during which various operations are performed on the molds, ware, etc., and to provide time for movement of the elevators.

Also, as heretofore mentioned, the pendulum is given a slight boost near the end of each swing so as to carry the weight somewhat beyond the ends of the normal path of its swing. The capacity of the cylinders necessary to provide the desired boost to the Weight is such however that it is difficult to provide the necessary flow of fluid to cause the pistons to keep pace with the pendulum, unless excessively large pumps are used. To avoid this the piston rods 49, as indicated at 49a, are extended into cylinders |20 and |20EL of smaller diameter, which are connected into the hydraulic system. These latter cylinders have a smaller capacity than cylinders 50--50a and are capable of causing the piston apply some little force to the pendulum. By-passes |2| and |2|a and by-pass valves |22 and |22@L are provided for the cylinders 5U-50a, and it will be apparent that when these valves are opened, as is the case when cylinders IN2-|20El are operating the larger pistons, the fluid will ow from one end of the cylinder to the other, thereby avoiding any drag on the pendulum and at the same time maintaining cylinders 50 and 50a in condition to give the desired boost to the pendulum when the valves in the system are operated to inject fluid pressure behind the pistons in cylinders 50-508.

The supply tank of the system is indicated by the numeral |23, and the fluid employed is preferably oil. From the tank |23 a line A, with suitable branches, leads to pumps B, C, and D operated by a motor M. And it should here be noted that the pump D is hooked up with the the two pumps B merely for the purpose of increasing the capacity of these pumps. As indicated on Figure 14, the pumps C are used in conjunction with the elevator-operating cylinl1 ders 82 at theY opposite ends of the apparatus. A pipe line E. connects with the pumpsV B, and with this line is connected line F which leads to the rear ends of cylinders |20 and |255. A pipe Y line G leads to the rear ends of main cylinders Eil-55a, and a line H leads to the forward ends of these cylinders. Connected with the line H is a line I which connects with line J leading to the forward ends of cylinders |2i) and |2522 As shown in the drawings, various check valves |24, arranged to open and close in the proper direction, are mounted in the several pipe lines. Also mounted in the system is the main pump 4-way valve |25, controlled by an electric system. Also connected in the pipe lines are relief valves |26, stop valves |21 and |21 (solenoid operated), a pump unloader or dump valve |28 (solenoid operated), retarder valve |29 (solenoid operated) and small pump C diverter valve |30, which is also operated by' a solenoid. The func.- tion of these several valves in the operation of the hydraulic system relating to the pusher bars, etc., will now be described.

Assuming the pendulum 5| is ready to begin its forward swing, the weight locks 60 are automatically withdrawn from the path of the pendulum, the valve |25 is opened and stop valve |21 for the rear ends of cylinders 5B-55e, is closed, and the stop valve |27 to the opposite ends of these cylinders is opened; iiuid pressure therefore travels from line E to line F to the rear ends of auxiliary cylinders mii-425e. The by-pass valves |22 and |222' are now opened by the operation of solenoids, to allow the oil to be transferred from the front to the rear ends of the main cylinders. The weight 5| thus swings forward, aided to some extent by the impulse from cylinders Mil-mea. Shortly before the weight reaches the extreme end of its forward swing the by-pass valves are closed, and at this time the stop valve |27 is opened and pressure is applied to the rear ends of cylinders 5|) and 5|)a as well as to the cylinders Wil-|2511 and the weight is pumped up to its proper destination. Fluid in the forward ends of the main cylinders is relieved throngh'pipe H and its check valve .|24 through li-way valve |25 to the tank |23,

and in order to prevent the pistons from hitting the ends of their cylinders too violently the retarder valve |29 is provided on the pressure side of the pumps to momentarily bleed 01T some of the pressure being directed to the cylinders.A

This valve of course functions on both the forward and reverse swings of the pendulum. During the application of pressure to the rear ends of the auxiliary cylinders, the uid in their forward ends is relieved through pipe jli-ne J, valve |25 to the return line and supply tank |23.

The dump valve or pump unloader valve |28 is closed during the irst ve seconds of a cycle of operation, namely, during the forward and rearward swing of the pendulum, and is then opened.

At the termination of the forward stroke of the pendulum the e-way valve |25 is closed or put in neutral position, and the apparatus is ready to begin the reverse movement to bring the pusher bars 55 into position for the next niove-` ment of .the mold trays.

In this reverse movement, the fi-way valve |25 is opened, stop valve 27 is closed, and stop valve |21 is opened; iiuid pressure therefore travels from line E to line J to the forward ends of auxiliary cylinders MGF-425@ The bye-pass valves |22 and |22a are now opened to allow the oil to be transferred from the rear to the ,front ends of the main cylinders.' The weight 5| thus swings rearwardly, aided by the impulse from cylinders |2{|-|20f1. Shortly before the weight reaches the extreme end of its rearward swing the by-pass valves are closed, and at this time the stop valve |21 ,is opened and pressure is applied to the forward ends of the main cylinders as well as the auxiliary cylinders, and the weight is pumped up to its proper position at the termination of the rearward swing. Fluid in the rear ends of the main cylinders is relieved through pipe G and its check valve |24 and as in the forward swing the retarder valve |29 serves to slow down the movement of the pistons. `During the application of pressure to the for- Ward ends of the auxiliary cylinders, the iiuid in their rear ends is relieved through pipe F, valve |25, and the return pipe to the supply tank |23.

At the termination of the rearward stroke of the pendulum the Li-way valve is closed or put in neutral position, and the weight is maintained at the limit of its rearward swing for about five seconds.

The function of the small pump (C) diverter valve |39 is to divert the fiow of pressure from this pump to the main pump lines during the interval that the elevator at the remote end of the apparatus is at rest. It might also be mentioned that the four parallel pipes which are connected to the return line just below the tank and lead to the opposite ends of the several cylinders are provided so that in the event power should be shut off, for any reason, during a swing of the pendulum, pressure fluid can be drawn into the cylinders from the low pressure side of the system, by suction created by the pistons, thereby avoiding uncontrolled swinging movements of the pendulum.

In the course of movement of the trays through the machine the molds must be cleaned and then dusted with powder such as lamp black or the like, and the molds must be closed and filled. After a portion of the moisture has been absorbed by the plaster-of-Paris of the molds, the mold funnels are cleaned, the molds are then opened and a trade-mark stamped on the ware; thereafter jets of warm air are projected directly onto the ware, and the ware is then removed from the molds, and fettled, inverted, and stacked, and removed to a firing kiln. The molds must then be again cleaned and the entire process repeated.

All of these steps of the process are performed automatically by various work units which are incorporated in the machine and timed to operate in the desired sequence. These various work units are not described herein as they are the subject-matter of other divisional applications or of my parent application Serial No. 580,4()1. The present invention is concerned largely with the manner of operating the machine to get the molds therethrough in a way that permits the various operations to be performed on the molds. It is believed the apparatus and its mode of operation will be fully understood from the foregoing description, and therefore only a very general outline of the operation will'be given below.

When the stops @e are withdrawn the weight 5| and the pendulum will swing forwardly, being aided by the hydraulic system, as previously mentioned. This forward movement of the pendulum will cause one operative stroke of each of the ten pusher bars 35. The pendulum then immediately returns to its original position, thus resetting all of the pusher bars in preparation for another operative stroke thereof. In this forward movement of the pusher bars a tray was moved from the elevators at opposite ends of the machine, onto each of the ten tracks. and as each tray was moved onto its track it caused a tray to be moved from the far end of that partciular track onto an elevator. The pusher bars remain in their retracted position for about five seconds, and during this period the two elevators, at opposite ends of the apparatus, will move the various trays, which have just been placed thereon, to the next track level, ready to be placed thereon by the next operative movement of the pushers bars. In this movement of the pusher bars a tray was moved from the elevators onto each of the tracks, and a tray was moved from the far end of each track onto the elevators.

Of course, timing mechanism and safety mechanism are employed in order to insure the proper operation of the various parts, and to cause the entire machine to shut down in the event that the proper sequence of events is for any reason disrupted. Neither the timing mechanism nor the the safety mechanism form a part of the present invention, and hence a disclosure thereof is unnecessary, and particularly so as the electric timing and control systems comprising interlocking circuits and switches operated by moving parts of a machine, are more or less conventional.

In accordance with the patent statutes I have described what I now believe to be the preferred form of the invention but inasmuch as various changes and modifications may be made in the construction without departing from the spirit of the invention, it is intended that all such changes and modications be included within the scope of the appended claims.

What I claim is:

l. In a pottery fabricating machine, a plurality of trays for supporting molds, a track upon which said trays are slidable, intermittently operated means at one end of the track for pushing the trays along the track in a step-by-step movement. and a cylinder-operated lever at the opposite end of the track for engaging the tray at that end of the track and compacting the line of trays.

2. In a pottery fabricating machine a plurality of trays for supporting molds, a track upon which said trays are slidable, intermittently operated means at one end of the track for pushing the line of trays along the track in a stepby-step movement, a cylinder-operated lever at the opposite end of the track for engaging the tray at that end of the track and compacting the line of trays at about the time they are to be moved forwardly, and a latch for engaging the last of said line of trays after it is so moved so as to prevent backward movement thereof.

3. In a pottery fabricating machine a plurality of trays for supporting molds, a track upon which said trays are slidable, an intermittently operated pusher bar at one end of the track for pushing the line of trays along the track in a step-by-step movement, a latch for engaging the last of said line of trays after it is moved. and a plate carried by the pusher -loar to press the latch against said tray when the pusher bar is retracted to operative position.

4. In a pottery fabricating machine a plurality of trays for supporting molds, a track upon which said trays are slidable, an intermittently operated pusher member for pushing the line of trays along the track in step-by-step movement, and a cylinder-operated lever on the remote end of the pusher member to engage the adjacent tray and compact the line of trays prior to a forward movement of the pusher member.

5. In a pottery fabricating machine, a plurality of trays for supporting molds, a track upon which said trays are` slidable, an intermittently operated member for pushing the line of trays along the track in step-by-step movement, said member including a substantially rectangular frame extending the length of the track, a pusher bar on one end of the frame for pushing the line of trays, and a cylinder-operated lever on the opposite end of the frame for engaging the first tray and compacting the line of trays prior to the operation of the pusher member.

6. In a pottery fabricating machine a plurality of trays for supporting molds. a track upon which said trays are movable, a pusher bar for moving the trays along the track in a step-by-step movement, a shaft, an operative connection between said shaft and the pusher bar, a pendulum connected with said shaft for oscillating the same, and a hydraulic control system operatively connected with the pendulum.

7. In a pottery fabricating machine a plurality of trays for supporting molds, a track upon which said trays are movable, a pusher bar for moving the trays along the track in a step-by-step movement, a shaft, an operative connection between said shaft and the pusher bar, a pendulum connected with the shaft for oscillating the same, a hydraulic control system operatively connected with said pendulum, and a lock automatically positioned immediately below the pendulum at the end of each of its movements for supporting the same under certain conditions.

8. In a pottery fabricating machine a plurality of trays for supporting molds, a track upon which said trays are movable, a pusher bar for moving the trays along the track in a step-by-step movement. a shaft, an operative connection between said shaft and the pusher bar, a pendulum connected with the shaft for oscillating the same, a hydraulic system including a pair of cylinders and pistons and a common piston rod, said piston rod being operatively connected to said pendulum, one of said cylinders and pistons being of sumciently small diameter to cause the piston to apply force to the pendulum at the rapid portion of its swing, and the other cylinder and piston being sufficiently large in diameter to lift the pendulum to the limit of is amplitude of movement.

JAMES A. BOWER.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 847,786 Koepif Mar. 19, 1907 1,837,605 Baker Dec. .22, 1931 1,926,215 Stoll et al Sept. 12, 1933 1,998,912 Troy Apr. 23, 1935 2,310,055 Bausman Feb. 2, 1943 FOREIGN PATENTS Number Country Date 397,032 Germany June 13, 1924 

